1. Field of the Invention
The present invention relates to a printing apparatus which conveys a sheet and forms an image on the sheet.
2. Description of the Related Art
In order to realize formation of a high-grade image by a printing apparatus, a sheet-like printing medium (herein, simply referred to as a “sheet”) is required to be conveyed with high accuracy.
Recently, in order to improve accuracy in conveyance control, a direct sensor which performs direct detection of a movement amount of the sheet has been realized practically. The direct detection is conducted by imaging a surface of the sheet so as to perform image processing on the image of the sheet surface. For example, U.S. Pat. No. 7,104,710 discloses a technology for performing the conveyance control using the direct sensor. In an apparatus disclosed in the above-mentioned U.S. Patent, the direct sensor is provided on a carriage in which a print head is installed, or at a position which faces a surface of a discharge port of the print head.